Thermal imaging devices, such as IR cameras, might be used for detecting gas occurrence, for example in the form of a gas cloud or gas plume e.g. from fugitive gas emissions or gas leaks, and for producing a visual representation of such gas occurrence as a gas infrared image. Such a gas infrared image can be used for visualizing gas occurrence or gas leaks, e.g. as smoke or a cloud on images presented on the viewfinder of a camera, on an integrated or separate display, or on an external computing device, thereby allowing the user to see gas occurrence in a scene observed and imaged by means of an IR camera. A variant of such techniques is called passive infrared gas imaging and is based on using radiation from a scene without any additional illumination for detecting gas.
Gas detection IR cameras, which are able to produce a full picture of a depicted area with gas appearing as smoke on the camera's viewfinder, have been provided. Two main types of cameras have been developed which operate in different wavelength bands; the mid-wave infrared band, 3-5 μm, and the long-wave infrared band, 7-14 μm. These cameras, which utilize a narrow-band spectral filter to single out the wavelength of interest, are able to detect and to visualize gases.
There is a need to improve the performance of IR cameras when in use for gas detection in gas imaging.